The goal of our research is to discover new and better ways to control and optimize photoinduced processes in organic materials. Our research involves both the synthesis of new materials and the use of laser spectroscopy and microscopy to study dynamics.
This work has practical applications in

the creation of photomechanical nanostructures

the conversion of solar energy

photoprotection against skin cancer

Nanomolecular Photomechanical Ratchets

In a spin: Slow pH-driven reprecipitation of 4-fluoroanthracenecarboxylic acid from aqueous solution results in the growth of branched microcrystals. The twisting of the branches under illumination drives a rotation of the overall crystal, as seen by optical microscopy, and can be repeated by repeated pulses of light. In the example shown, an X-shaped molecular crystal undergoes a net clockwise rotation of 50°

Photomechanical structures may provide self-assembled nanomachines that could potentially do useful work.

Reshaping the Solar Spectrum:A hybrid molecule combines inorganic semiconductor nanocrystals with organic emitters to "reshape the solar spectrum" so that it better matches the materials used today in solar cells. It works by first capturing two infrared photons that would normally pass right through a solar cell without being converted to electricity, then adds their energies together to make one higher energy photon. This upconverted photon is readily absorbed by photovoltaic cells, generating electricity from light that normally would be wasted.